mike tkach

scott,the supercharger,no matter the type or brand forces the air-fuel charge in the cylinder .as you said simple physics,the more air-fuel you put in the cylinder the more power it will make.for a n/a engine to achieve a ve similar to the boosted engine it needs much more cam.it also needs a higher compression ratio but thats for another day.what i am saying is the supercharged engine requires way less lift&duration than the n/a engine so even though their is more pressure against the exhaust valve it is still easier on the rest of the valve train than the n/a engine.example,try running a hyd roller on an engine like apache 14 has and see how long that will last,my bet is not long.the 262-270 at .050 with .647 lift hyd roller in my boosted 1200+hp engines won,t make power in his engines,simple physics!i agree with your statement that the boosted engine[ if it has a belt driven supercharger] makes more power at the piston,that is why i made my comment about using the right parts.does that hold true if the boost comes from a turbo charger?

horsepower1

Two comments that I saw that got my attention in this discussion; n/a motor with "equal power" as a blower motor, and "use the right parts". All I was pointing out was there needs to be a alittle more thinking about these comparisons than face value, ie: the blower motor has to make more power (at the piston, where all the work is done) to have the same measured power as an NA engine, so that's not really a fair comparison. It's apples and oranges. Second, qualifying the comparison by saying "if the right parts are used" as if they wouldn't be for one engine, and would for the other in the comparison. I would expect that the "right" parts would be used in either engine, according to the needs of the build.
Turbo engines have a unique circumstance where they run under back pressure during overlap and the piston isn't trying to come off the end of the rod when it changes direction like on other engines. Turbo engines are a lot easier on bottom ends but have their own need as far as reliability and longevity. Cyl pressure is cyl pressure.

ICDEDPPL

Whats a typical roots blower lets say 10-71 eat for horsepower at 1:1 ?
50hp?

mike tkach

good discussion scott.i guess be it 1200 hp n/a or supercharged it will be hard on parts,if not everybody would have them.

mike tkach

i can,t answer that but i read that the supercharger on a top fuel engine uses 1100 hp at 8000 rpm.

mike tkach

dan,i can tell you that my spare engine made 1015 hp with the 16.71 and 1200+with the 8.3 whipple due to the difference in parasitic loss in the superchargers.the 16.71 eats power and generates heat,the whipple does neither.

horsepower1

Probably closer to 150

mike tkach

takes power to make power,lol.

phragle

All this motor stuff has ruined car commercials for me.... just saw one on tv enthusiastically claiming 320 hp,, voice in my head went 320hp? your bragging about 320 hp.. lol

phragle

In physics, the law of conservation of energy states that the total energy of an isolated system remains constant—it is said to be conserved over time. Energy can neither be created nor destroyed; rather, it transforms from one form to another.